Grinder mechanism.



F. W. REDSHAW.

GRIND-ER MECHANISM. APPLICATION man mum. 9n.

Patented May 29,1917.

In: Nokms PETERS m. mamuma. wasnmcmmn. c

UNITED, s'rarns raann'r orrion.

FREDERICK w. REDSI-IAW, or SCOTTDALE Boaouen,rn NNsYLvANIA.

1 GRINDER MECHANISM.

Specification of Letters Patent. I I Patented May 29, 191% AppH eati on'filed January11,' 1917. SeriaINo.141,736. 7

To all whom it may concern: 7

Be it known that I, Fiinnnarok V. RED- sHAw, a citizen of the United States, and residing in Scottdale Borou gh, in the 7 county of \Vestmoreland and State of Pennsyle vania, have invented or discovered new and useful Improvements in .Grinder Mechation.

My invention consists in anew and improved portable grinder mechanism for jointer and planer knives.

The object which I have in view is the provision of a portable sharpening attach ment which may be quickly mounted on a jointer or planer, and as quicklyv dismounted, and which will accurately grind and balance the knives without requiring their removal from the head.

In machinery of this character, it is nec essary that the knives be accurately alined and balanced, and, if the knives be removed from the head for sharpening, the proper resetting of the knives is a tedious operation and one beyond the skill. of the ordinary mill mechanic. It is desirable, therefore, to grind the knives without removing them from the head and also without removing the head from the machine.- In the use of a portable grinder for this purpose, the same must be capable of positive positioning in relation to the knives, so that no variation or inaccuracy can possibly occur, and the mounting of the grinding member must be such that-it will run true in all positions, so that the sharpened knife will be properly balanced. v

I accomplish the object in view by providing a relatively light weight grinder mechanism which is conveniently portable and which, when mounted on the jointer or planer positively assumes andmaintains the eXact position required for the accurate sharpening and balancing .of the knives. The frame of the mechanism is rigid or integral to prevent loss of alinement or movement of itsparts, and it is provided with fixed means which engage recesses in the jointer or planer and positively fix the position of the frame in relationto the knives to be sharpened. A driven shaft is mounted in said frame and an emery wheel is mounted or said. shaft to rotate therewith,

nism, of which the following is a specificaand to he slid along the length thereof by means of a yoke which is slidably, mounted on said driven shaft and on a guide shaft parallel-with, said driven shaft.

' Novel features of construction and arrangement of parts will appear from the following description.

In the accompanying drawings Figure 1 is a rear elevation showing my lmproved grinder mounted on the back bed of a jointer, tlie bedand one of the knives being shown in dotted lines; Fig. 2 is a vertical section along the line IIII inFig. 1, the front and rear beds and the rotary head with one of its. knives being shownin dottedlines, and F 3 is a broken vertical section through the axis of the emery wheel to show its mounting. on the driven shaft.

The following is a detailed description of the drawings. I A represents the rear bed of the jointer; B the front bed of the same; C the rotary head, and D one'of'the knives mounted in said head.

In machines of this kind, adjusting mechanism-is provided whereby the beds be kept accurately positioned and leveled in relation to the head and its knives. I do not show such mechanism as it is not in itself a part of the present invention.

' Referring now to my grinder mechanism, E is acast metal frame, preferably integral but which, if so desired, may be built up of elements which are rigidly connected together so that no movement or vathe jointer or planer,.res'ts flat upon and is positioned transversely of the rear bed A in parallelism with the head D. The lower face of said base lisprovided with a plurality of depending dowels or projections 2 which engage accurately fitting recesses or holes 3 cut into the bed A. 4 are set screws extending through the base I and engaging threaded'holes 5 in the bed A.

It is perfectly evident that, by the combined use of the dowels and" set screws thev f me m bQb -h fi m yc amp d a d -Q- were p sifm tl are wer ever the grinder mechanism is mounted on the jeinter or planer, it will always assume and maintain the same exact position.

6 and 7 represent a pair of brackets, integral with and extending forwardly from the base 1 so as to occupy vertical planes beyond the ends of the knife when the grinder mechanism is in position for use. The outer ends of said brackets are provided with alined bearings 8 and 9. 10 is a third bracket spaced outside of bracket 7 and parallel therewith. 11 is a bearing in bracket 10 alined with bearings 8 and 9. 12represents bushings inserted in bearings 6, 7 and 10.

13 is a rotary shaft journaled in bushings 12 and held against longitudinal movement by set collars 14L fixed on the ends of the shaft. 15 is a pulley or band wheel rigidly fixed on the shaft 13 between the brackets 7 and 10, whereby rotation may be imparted to the shaft 13. The pulley may be op erated by a belt from the counter shaft of the jointer.

F is an emery wheel or other rotary grinder mounted on said shaft 13 so that it rotates with said shaft and may be slid along the same at the will of the operator. Thus, I have shown the emery wheel provided axially with a cylindrical lead core 16 within which is a paper lining 17 and a metal bushing 18 threaded at either end for the application of lock nuts 19. 20 is a feather key fixed to and extending inwardly from the bushing 18 to engage a slot 21 cut in the shaft 13 and extending between the brackets 6 and 7. Thus the grinder rotates with the shaft 18 and may be slid along the same between the brackets 6 and 7.

G is a bifurcated carriage provided with parallel arms 22 which form a yoke which encompasses the axis of the emery wheel F. Said arms are provided with snugly fitting bearings 23 through which the shaft 13 extends, thus slidably mounting the carriage on the shaft 13.

24 is a fixed shaft, parallel with shaft 13 and having its ends secured in the bases of the brackets 6 and 7. Said shaft 24 extends through a snugly fitting transverse hole 25 in the carriage Gr. 26 is a handle or hand grasp fixed to said carriage.

It is evident that while the-emery wheel F is revolving, it may be slid along the shaft 13 to reach and grind every portion of the knife edge, by moving the carriage G, the shafts 13 and 24 acting as guides to prevent lateral swaying movement of the wheel out of a true vertical plane.

It is evident from the foregoing that my grinder mechanism is relatively light in weight, of very economical and durable structure, and may be readily mounted on or dismounted from the jointer or planer without requiring delicate adjustment or positioning. It may be set down into place with positive. assurance that the knives will be ground true and perfectly balanced. The frame is perfectly rigid and contains no parts capable of adjustment or change. The emery wheel, being controlled by a carrier which is transfixed by parallel shafts, slides readily along the driven shaft without lateral sway or movement out of a true vertical plane. swaying or inclination would result in an uneven cutting edge for the knives.

What I desire to claim is 1. A grinding mechanism for sharpening the knives of jointers and planers without removing the latter from the machine, and comprising a fiat base plate adapted to be laid transversely on the bed of the machine, adjacent and parallel to the rotary head thereof, and provided with depending positioning dowels, the bed of the machine boing provided with holes to receive said dowels and accurately position the base plate of the grinder, means independent of said dowels and holes for holding said base plate rigidly on said bed, a pair of brackets permanently rigid with said base plate and so located as to extend one at either side of the bed plate of the machine, a third similar bracket spaced outwardly from one of said first named brackets, a rotary shaft journaled parallel with said base plate in all three of said brackets, a power pulley rigidly mounted on said shaft between said third bracket and the adjacent one of said first mentioned brackets, a grinding wheel slidably mounted on said shaft but rotating therewith, a bifurcated carriage embracing said wheel and slidably mounted on said shaft, a guide shaft parallel with said first mentioned shaft and extending between the first mentioned pair of brackets, said carriage being provided with a horizontal hole through which said guide shaft extends, and a hand grasp for said carriage, substantially as and for the purposes set forth.

2. A grinding mechanism for grinding the knives of jointers and planers without removing the latter from the machine, and comprising a metal frame consisting of a flat base plate adapted to rest upon and This is very important as such transversely of the bed of the machine, said naled in all three brackets, a driving pulley rigid with said shaft between said third bracket and the adjacent one of said first mentioned brackets, a grinding Wheel sliding on and rotated by said shaft, a guide shaft mounted on said frame parallel Withsaid first mentioned shaft a carriage sliding on both of said shafts and controlling the sliding motion of said Wheel, and clamping means independent of said members and said recesses, for holding said grinding mechanism rigidly in place on said machine, substantially as and for the purposes set 10 forth.

Signed at Seottdale, Penna, this 5th day of Jan, 1917. i

FREDERICK W. REDSI-IAW.

Gopies of this patent may be obtained for five eents each, by addressing the Commissioner of Patents,

Washington, D. C. 

